Ventilator.



W. H. .DAVIDSON.

VENTILATOR. APPLCATION FILBD APR.10, 1908. V

Patented Sept. 15, 1908.

UN ITED 'STATES PATENT OFFICE.

WILLIAM DAVIDSON, OF BOSTON, MASSACHUSETTS( ENTILATOR.

T au wwm it may concern:

Be it lm0wn that I, WILLIAM H. DAVIDSQN, of Boston, in the county of Sufiolk and State of Massachusetts, have invented certain new and useful Improvements i11'Ventilators, of which the following is a spcification.

This invention relates to ventilators to be placed upon chirhneys or outlet fines of dwellings and other buildings; t0 cause an induced draft whereby to draw the foul air from a building orproduce a draft in a furnace.

The present invention is particularly adapted for use as a ventilator to' draw the air rom the rooms of a building and allow it to be replaced by fresh air.

The principalobject of the invention is to enable a ventilator of this kind to' be auto matically governed by the force of the Wind, so that approximately the same amount of air. will be withdrawn when the wind is light as when ittis liigh. T0 this-end the ventilator 1s prov1ded w1th a movable closure winch lnnits the draft openiiig more or less, according to.th.e velocity of the wind.

Another object is .to Permit regulation of the closure so as to make it sensitive in any required degree.

Still another object is to pr .dvide a shield for preventing the production of eddy cur rents, 'whichwOuld tend to impair the efi ciency of the draft, under highwind condiduced in area.

A further object is to permit additional tions when the draft outlet is materixlly reregulation of the ventilator under diflerent .conditions of external temperature so that in cold weather. the amount of induCeddraft may -be diminished to guard. against too great an inflow' of cold air being brought about.

- In the drawings "I have illustrated anombodiment (if the invention.

Figure 1 represents a side elevation of this embodiment. Fig. 2 represents a reat end eleVation of the same. 'Fig. 3 represents a vertical longitudinal section on an enlarged scale. Fig. 4 represents a rear end elevation; Fig. 5 represents a plan vie w in detail of the mechanism for adjusting the ventilator -to varing temperature conditions.

The same reference charactrs indicate the same parts .in all the figures.

Specification of Lettrs Ratert.

. tween the casings.

Patented Sept. 15, 1908.

Application filed April 10, 1908. ..j S eial No. 42'6,247.

The ventilatot consists of a main body or outer casing 1 Which is provided With an outwardly flarrng flange 2 at the front end, and is'contracted at the rear end by turning in a lip 3. Within the outer casing is an inner casing 4 which is openfrom end to end, and at itsiront end is fl.red outwardly to the outer casing, being peripherally connected thereto so as entirely'to close the front 'end of the space between the two casings. Tliis provides an annula i space or chamber 5 be- V The inner casing 4 is of less length than the. outer casing, and terminettes a oonsiderabl distance short of the contracted end of the latter. Thus the chamber 5 and the passage 6 throi1glrtlre inner casing, which passage 1nay conveniently be called the draft passage, join together in advance of the outlet. There is an opening 7 in the lower side of the main casing which communicates with the annlar chamber 5, and to which leads a tube 8 secured to the main casing. This tube telescopes over a fine 9 leadig iron1 the interior of a building.

The rear'end of the inner casing preferably extends beyond the rear limit of' the Opening draws air from the chamber 5, and therby induoes a fiow through the inlet 7 into the chamber, drawing vitiated air from the inte rior of the building through the fiue 9. The

flue 9, tube 8, inlet 7'and chambgr-5 thus con.

stitute an induction passage.

Extending across the ventilator between the:ends of-the casing is a conical bafile or valve member which is inounted as to be movable toWard and from the contracted outlet end of the ventilator to more or less close the latter. When moved to its fullest extent toward the contracted end, it serves as a closure to obstruct more or 1988 the outlet spaoe. The baffle is always -held so that it does not close the. end of the inner casing, but the latter is always open" and a dralt through the passage 6 is permitted as long ,as the bafiie is sufficiently romoved from the outlet 3 t0 permit flow thorefrorn. The external diameter of the baille is approxL mately equal to the outlet diameter of the main casing, and the rear end of the inner casin is also .shown as being of approximatey the same diameter. The baffle is permit the nocessary 1novement.

spring may force of the highest wind which is fiable to surrounds the 1car end of the barand bears between the guide and adjsting nuts 17, whereby its tension may be regulated. The spring normally holds the bnflle in the posit1on illustrated, at' the inner limit of its 5 travel, so that the space 'between its outer edge and the ventjlator outlet is as g1eat as that between the baille and the adjacent walls of the main casing, thereby giving the maximum induced dralt. When the wind increases beyond a certain amount, the ten sion of the spr1ng 16 'is overcome and the baffle movd toward the outlet of the main casing, -reducing the area of the outlet and diminishing the force of the draft. "HOW- ever, the dimensions and power of the spring are such as to prevent the baffle from moving quite to the end of the main casing, and so entirel shutting off the flow of air By adjustment of the nuts 17, the tension of the be made so as to balance the be met with, and to arrest the closing movement of the baffle before the outfloW from the induction passage is entirely shut Off. The

5 regulation may be of such an amount that the baille automatically adjusts itself- ;to winds of all degrees of force, so that the quantity of air drawn out through the induction passage may be maintained constant, what- 40 ever the conditions as to velocity of the wind may be. When the outlet is thus rstricted and the space between the baffle and end of the inner casing at the saine time enlarged, there is a tendency of the air. blowing into the draft passage to set up eddy currents and be blown back into the chamber 5, thus producing a dralt in the wrong direction. T0 guard against this result, I provide a shield 18 Which surrounds the rar end of the casing 4: and is connected to the baffle through the guides 11 by means of brackets 19.. These brackets arc slotted so as to per mit an adjustment of the shield With res ect to the baffle, by allowing tlie blts by WEGlI theshield is held to be slipped)ongitudi nally in the slots. Tlie adwstment thus governs the width of the space betweentl end of the shield and the baffle, and as the shield is in efi'ect a continuation of theinner 0 casing, it governs the spacebetween this casing andthe baffle. When-once adjusted, this space is invariable, because the shield travels With he baffle, and thefieforethe inner casing is lengthened When the outlet 5 from the main casmg is restricted.

varying atmosphcric conditions, there being mot niuch greater removal of air on windy and blustering days than when the atinosphere is comparatively still. Thus an excessive ail circulation, causing dralts, is not set up in a building When the Wind is very high, as would be -the case if; no provision were 1nade for automatically governing the draft opening.

It -is desirable also to limit the draft opening in cold weather so that a less amount of warm air will be Withdrawn, whereby to pre- 'vent the building becoming chilled to too great an extent. .To elect this result, I provide means capable of being manipulated .to move the baffle into partially closed position, and a retaining devic6for preventin it from withdrawing from this position, whie allowing it to be further closed by excessive air pressure. consists of a pinion 20 which is adapted to mesh with a series of rack teeth on the bar 14, which is connected withthe baffle. v This bar is-widened and centrally slotted so as to-em brace the pivot rod 22 on which the Ventilator is swiveled, and the pinion 20 -is carried by a sleeve 23.which surrounds this rod. Normally the pinion is below the rack and oflers no hindrance to theback and forth movement of the baffle and bar, but when it is raised, its teeth engage tliose of the rack, and when rotated, moves the baffle backward toward the outlet. The pinion is raised and t1iined thebafile, approximately the same The means for so setting thebafile by a drivin pinion24 meshing with a gear 25 on the basc of the sleeve 23.: The latter gear has a flange 26 projcting smew'lafiover the pinion 24, and this pinion is mouhted so that it can be lifted in its bearing. :27. t has a hub provided with 2; socket 28 into which an operating rod may be inserted. When the pinion 24 is raised, it lifts pinion 20 into. mesh with the raek, and when rotated, 'it turns the rack and moves the bafle. Upon withdrawal of the operating rod, the pinions drop and release therod 14. Retraction of the baffle is prevented by a pawl 29 which is pivoted t0 a c0llar 30 and engages teeth on the tail of the 'rod14. This collar is enabled to slip freely upon the rOd, and is c rdinarilhcld against the guide 15 by the spring 16 acting tlirough the teeth and pawl. A disk 31 is fastened to the sleeve 23 and acts as an abutment to pre- V6I1D the collar 30 being carried with the rod 14 during adjustment of the baffle. This disk 31 is lifted simultaneously with the pinion 20 so as to lie beside the lower part of col lar 30, thus causing the collar to remain stationary while the rod is drawn through it. The pawl 29 is sPring or. gravity actuated so as tongage the teeth automatically. It has a handle 33 from which a line 34 extends, the latter running down through the flu'e 9 1Q ble.

the interior of the building vvhere it is accessi- By'operating the pinion 20, the Ventilator may be more or less closed in ,cold

weather, and when the weather becomes warm, it may be opened by the spring 16, by simply disengaging the paWl by a pull on the line 34.

1. A ventilator consisting of a body'having' alongitudinal draft passage, an internal partition dividing OH an induction chamber 01 passage which is closed at the front and open at the rear or outlet of the ventilator, a side .opening for the admission of an indced current to the induction chamber, and a baffle in the draft passage movable by the force of the current flowing through suchpassage toward the outlet t0 restrict the same.

2. A ventilator consisting of an outr cas- 1ng, an 1nnr cas1ng open from end to and to prov1de a longitudinal draft passage and joined at its front or inlet and -to the outer opening through the sideof'the outer casing,

and a baflie betWeen the adjacent ends of the casingS movable by the force of the current fiowing through the 'ventilator toward the contracted and of the outer casing t0 obstruct more or less the outlat therefiom.

4. A ventilator consisting of a body having a longitudinal draft passage, an internal par tition dividing ofi an induction chamber or passage which is losed at the front; and open at the rear or outlet of the ventilator, a side opening for the admission of an induced cur rent to the induction chambar, a baffle in the draftpassage movable by the force of the currant fiowing through such passage toward the outlet to restrict the same, and means for praventing back drait in the induction pas sage when the outlet is restrictad.

-- 5. A ventilator consisting of a body having alongitudinal draft passage, anintarnal partition dividing off an induction chamber or passage which is Closed at thefront and open at the rear or outlet of the viantilator, a side opening for the admission of an induced current to the induction chamber, a bafiie in the draft passage movalal by the force of the current fiowing thiough such passage toward the outlet to restrict the same, and a member, operable upon movemarit of said bafiie in restricting the outlet, to extend said partition and prevant back draft in the induction chamber.

6. A ventilator consisting of an outer casa ing, an inner casing open from and to and to provide a longitudinal draft passage and and a tube talescopically arranged with re spact to said partition and connected to said baffle so as to be moved by thelatter, in its outletobstructing movemant, to increase the affective length of the partition and thereby prevnt back draft in the induction chambar.

"7. A ventilator consisting of a body having a longitudinal "drai t passage, an internal partition dividing off an induction chambar -or passage which is closed at the front and open at the rear or outlet'of the ventilator, a side opening for the admission of an induced cur rent to the induction. chamber, a baflle in the draft passage inovable by" the force of the current fiowing through such passage toward the outlet to restrict the same, and nonauto matic provisions for setting said baffle in accordanc with various weathar conditions.

8. A ventilator having a draft assa'ge and an induction passage with an in et opening into which air is drawri by flow of air through the drait passage, an obstructing device automatically niovable by the force of the air flowing through the draft passage to restrict the velocity of outfiow from the induction passage, yialding mearis tendig to return saiddevice, and a manually controlled stop for limiting the raturn thereof.

9. A ventilator having a draft assage and an induction passage with an in let opening into which air 1s drawn by flow of air through the draft 1passage, an obstructing device au tomatical r operated by pressure of the wind blowing through the dr aft passage to check the velocity of outfiow from the induction passage, and a datent manually operable to permanently restrict such'outfiow, while permitting furthar restriction automatically by wind pressure.

10. A cntilator having a draft passage and an induction asSage, and a valve member actuated by tiie Wind pressure for limit in'gthe oi1tfiow from the induction passage under high Wind conditions, together with means for,o posing the wind-caud movement of said valve member ar1d.prevanting complete stop age of the outflow.

11. A vent1 ator having a draft passage and an induction assage,'and a valve member actuated by t e wind pressure for limiting the outflow from the induction passage under high-Wind conditions, together with 

